1. Field of the Invention
The present invention relates to a terminal signal operation apparatus for transmitting in both directions through a multiplex transmission system between the terminal signal operation apparatus and a central processing apparatus in order to control a plurality of electrical devices.
2. Description of the Prior Art
In general, the various control apparatus for the electrical devices of vehicles e.g. cars, ships and airplanes are quite complicated with the result that the wiring therefore is difficult to install and difficult to maintain in proper working order. It is believed that the use of a multiplex transmission system can alleviate much of the complexity. It is also believed that the use of devices to detect malfunctions would also be quite helpful. In order to accomplish this, it is necessary to have a transmitting device for transmitting a multiple signal; a receiving device for controlling the electrical devices in accordance with the multiple signal; and a malfunction signal returning device for returning a malfunction signal upon detection of a malfunction of the electrical device.